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ASHWINI's avatar
ASHWINI
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7 years ago

PCI Scrambler

we are developing some custom PCIe application where we can't use hard PCI ip so as which will be tested on stratix 10 SX dev kit.

while searching scrambeler in intel exmple code for PCI we got one pipe_scrambler. v file, in that they implemented Addtive LFSR, i want know that which polynomial used for that LFSR? and what is words_pld_if,pld_if_dw? can u explain me

2 Replies

  • Nathan_R_Intel's avatar
    Nathan_R_Intel
    Icon for Contributor rankContributor
    7 years ago
    Hie, My apologies for the delayed first response. I got your case mixed up with another PCIe forum question; hence I missed providing an update. I am sorry, but I cannot identify which portion of our IP, reference design or Quartus version where you have obtained this .v file from. Anyway, for Intel-FPGA's PCIe IP, the polynomial used is a degree 23 polynomial for LFSR for scrambling. For this .v file, it has data_out width of 32 bit. pld_if_dw is parameter specifying the interface data-width. words_pld_if is another parameter to specify the scrambler data enable width. Regards, Nathan